Page Numbering Math Problem

MediumPython

Problem

It takes 1000 digits to number the pages of a book consecutively. How many pages are there?

Implement count_pages(total_digits) to return the page count when numbering starts at 1. Return -1 when no whole page count uses exactly that many digits, and return 0 when total_digits is 0. The input is a nonnegative integer.

Constraints

0 <= total_digits <= 10^18
Page numbering starts at 1
Pages are numbered consecutively without skipped numbers
Return -1 when the digit count ends partway through a page

Function Signature

def count_pages(total_digits):

CodePython 3

You need to log in / sign up to run or submit.Ln 2

Run your code to see test output here.